1. Field of the Invention
The present invention relates to a diamond cutter, and more particularly to a disc shaped diamond cutter to be used to cutting concretes, building stones, firebricks and others, or to drawing lines in asphalt pavement when breaking it.
2. Description of the Prior Art
The above mentioned sorts are provided with man-made diamonds on a circumferential part of a circular base plate. There are two types, and one of them is that the base plate is formed with a groove on its circumference, and grinding grains are adhered therein, while on the other hand, many arc tips with grinding grains are attached by melting the grams onto the circumference of the base plate. In the both, the friction heat of high temperatures is caused during cutting in the circumferential part of the base plate. Therefore, conventionally, many radial slits 1 have been extended from the circumference toward the central part thereof (FIG. 1). This manner succeeded in releasing the heat to some extent, but the residual heat in the slit 1 was transmitted to an axial hole 2 and brittleness was caused and crackings were invited there. Such inconvenience was more remarkable when the water was not supplied to the cutter during the work (dry system), especially in order to prevent pollution.
Further, since the outermost circumferences were in arc shape in every case, the cutting ability (biting) was unsatisfactory. Thereupon it is assumed that saw shape is applied to a cutting edge in order to increase the cutting ability. If the cutting edge is made actute angled, the cutting ability will be increased, but it will be easily broken, and any measures are wanted.